Granada, Toledo, and Salamanca were also important centres, to which students flocked from western Europe.

It was the proximity of these Arabian centres that stimulated the scientific interests of Alfonso X.of Castile, at whose instance the celebrated Alfonsine tables were constructed.

A familiar story records that Alfonso, pondering the complications of the Ptolemaic cycles and epicycles, was led to remark that, had he been consulted at the time of creation, he could have suggested a much better and simpler plan for the universe.

Some centuries were to elapse before Copernicus was to show that it was not the plan of the universe, but man's interpretation of it, that was at fault.
Another royal personage who came under Arabian influence was Frederick II.

of Sicily--the "Wonder of the World," as he was called by his contemporaries.